昆明城区颗粒物质量浓度变化特征及驱动因素研究

Study on the Variation Characteristics and Driving Factors of Near-surface Atmospheric Particulate Matter Concentration in Kunming Urban Area

为探究颗粒物对昆明城区环境空气质量的影响,基于2015~2020年颗粒物质量浓度数据,利用Spearman相关性分析、冗余分析方法对颗粒物质量浓度时空变化特征及其驱动因素进行深入研究。结果表明:2015~2020年期间,可吸入颗粒物(PM_(10))、细颗粒物(PM_(2.5))质量浓度均呈现显著下降的变化趋势,年内旱季整体高于雨季,日内呈“双峰双谷”波动变化趋势且夜间显著高于白天;颗粒物质量浓度的主要影响因素是风速,并与降水量、相对湿度、气温呈现显著负相关,但也受到区域传输、人类活动等多种因素影响。未来,应分区域、分时段(旱季和雨季、昼间和夜间)制定差异化的污染管控措施,重点控制PM_(10)质量浓度并使PM_(2.5)质量浓度持续下降,为持续提升昆明城区环境空气质量水平提供科学依据。

In order to explore the impact of particulate matter on the ambient air quality in Kunming urban area,based on the particulate matter concentration data from 2015 to 2020,spearman corelation analysis and redundancy analysis were used to conduct an in-depth study on the temporal and spatial variation characteristics of particulate matter concentration and their driving factors.The results showed that the mass concentrations of inhalable particulate matter(PM_(10))and fine particulate matter(PM_(2.5))presented a significant decreasing trend during 2015~2020,and the dry season was generally higher than the rainy seasonduring the year,and both showed a"W"shape(double peaks and double valleys)during the day,and the night was significantly higher than the day.The main influencing factor of particulate matter concentration is wind speed,which has a significant negative correlation with precipitation,relative humidity,and air temperature,it is also affected by various factors such as regional transmission,human activities,etc.In the future,differentiated pollution control measures should be formulated in different regions and periods(dry and rainy seasons,day and night),focusing on controlling the concentration of PM_(10) and continuously reducing the concentration of PM_(2.5),so as to provide a scientific basis for continuously improving the ambient air quality level in Kunming urban area.